Optimal Zone Research Articles

Precise classification and regional delineation of maturity groups in soybean cultivars across China

The maturity group (MG) system is a widely recognized and effective approach for assessing the photothermal sensitivity of soybean cultivars and determining their optimal adaptation zones. In China, soybean have been cultivated extensively for thousands of years, evolving into various ecotypes through natural and artificial selection. In this study, the relative maturity groups (RMGs) of a total of 766 soybean cultivars collected from the Northeast Spring Planting Sub-region (NE), Huang-Huai-Hai Summer Planting Region (HH), Northwest Spring Planting Sub-region (NW,), and South Multiple Cropping Region (SC) of China were evaluated using linear regression models at 36 sites nationwide. The results show that the RMGs of Chinese soybean cultivars range from MG m1.6 to MG 9.5. Among all the identified soybean cultivars, MG III cultivars account for the largest proportion of 22.19 %, followed by MG II (21.67 %) and MG I (18.54 %). Conversely, MG IX has the fewest number of cultivars, representing only 0.26 % of all cultivars. The MG ranges for spring- and summer-sowing cultivars are MG 000-V and MG II-IX, respectively. The adaptive soybean MG zones across China were mapped using the method of Kriging interpolation based on the soybean RMGs data from 816 sites of 29 soybean-producing provinces. Cultivars of MG 0 and earlier groups are primarily distributed in the NE, and MG III and MG IV are the major MGs in HH and NW. The cultivars in MG V and later groups mainly distribute in SC. This study realizes the unification and normalization of the MG system between China and other major soybean- producing countries worldwide. Such unification and standardization will facilitate global germplasm exchanges and assist soybean producers in making more informed decisions when selecting cultivars.

Integrating Agricultural and Ecotourism Development: A Crop Cultivation Suitability Framework Considering Tourists’ Landscape Preferences in Qinghai Province, China

Ecotourism and agricultural development have been proven to have synergistic effects, although few studies have employed a spatial planning approach to incorporate tourism growth into crop cultivation planning. This study constructed a theoretical framework of environmental suitability—farmland accessibility—tourist’s landscape preferences for crop cultivation planning to link regional agriculture and ecotourism development. The spatial planning of rapeseed cultivation in Qinghai Province was chosen as a case study. The main research methods include an environmental suitability analysis based on remote sensing and Maxent modeling, a farmland accessibility analysis based on a GIS platform, and a landscape preference questionnaire survey of tourists. According to the survey’s findings, almost 80% of tourists thought rapeseed flowers enhanced the beauty of natural landscapes. This demonstrated the enormous potential of rapeseed fields for fostering ecotourism. Based on environmental factors, the optimum region for rapeseed cultivation covered 5.38% of the study area, or roughly 6327 km2. The comprehensive optimum zone, which encompassed both agricultural accessibility and environmental suitability, was equal to 12.63% of the study area’s farming area, or around 929 km2. This study’s crop cultivation suitability framework can integrate agricultural and ecotourism development, with substantial implications for achieving coordinated economic, social, and environmental development.

Exploring the combination and heterogeneity of ecosystem services bundles in the Beijing-Tianjin Sandstorm Source Control Project

The relationships among ecosystem services (ESs) and their spatiotemporal dynamics plays an essential role in ESs management. However, it is difficult to characterize the spatial composition of ecosystem services bundles (ESB), clarify the complex relationships and their driving forces. This study estimated 6 specific ESs of Beijing-Tianjin Sandstorm Source Control Project (BTSSCP) based on related models, using conjunction operations identified ESB, finally explored the trade-offs and synergies between ESs within each ESB, and furtherly suggested different management zones in terms of ESB types. The results indicated the values of all six key ESs have improved from 2000 to 2015, and shown a decreasing trend from the southeast to the northwest accompanied by expansion trend of the high value region. Additionally, ESB dominated by sand-fixing service were primarily distributed in the southwest and showed a trend of continuous and significant expansion from southwest to northeast during 2000–2015. And, wind speed, soil types, slope, vegetation types and population density are the main driving factors of ESB changes. What’s more, trade-offs and synergies among ESs appears the characteristics of spatial heterogeneity, especially between sand-fixing service and Net primary productivity, which presenting synergistic promotion relationship in bundles 1 and 2, while significant trade-offs in bundles 3 and 4. Finally, we divided BTSSCP into three zones—key improvement zone, ecological conservation zone, and integrated optimization zone based on ESB as per the regional sand-fixing capacity, enhancement potential and the relationship between ESs, and proposed specific suggestions for management in various ESB, which are beneficial to regional sustainable development and appropriate management.

The Fuzzy Model for Sectoral Resilience Analysis

The report describes a process of analyzing sectoral resilience using the strategic matrix model of 4x6. It presents the main measures at the government level that can contribute to the restoration of sectoral resilience in the event of unfavorable impacts such as military, natural, or technological incidents. Methods. The 4x6 matrix is an oriented graph, with nodes representing the matrix indicators distributed across the matrix cells, and edges representing the links between indicators. The model is dynamic and positioned in discrete time, with the unit of measurement being a year. The matrix models the industry as a cybernetic system with positive and negative feedback loops. Negative feedback loops are generated based on anti-risk management results. Positive feedback loops arise in two ways: a) reinvesting net profits in business and increasing equity; b) proactive decision-making. The report presents a simple example of a sectoral matrix consisting of 15 indicators connected by 22 links. It demonstrates the anti-risk and proactive management of industry resilience by the state, through public-private mobilization partnerships (PPMP). The paper examines the positive impact of the following measures on industry resilience: a) price regulation; b) return industrial mortgage; c) government supply chain factoring; and d) government leasing. The relationship between efficiency, resilience, risks, and opportunities is ambiguous. It is necessary to research the optimal zones where an acceptable value of all four factors can be preserved at the same time. Resilience is lost in both positive and negative senses; progress occurs in leaps, and new qualitative heights in business are achieved through repeated growth of all types of risk accompanying that business. In this case, stabilizing measures can hinder reaching new heights. The proposed modeling technology allows for the analysis of cross-industry interaction, including the creation of cross-industry syndicates (clusters).

Carbon Emission Patterns and Carbon Balance Zoning in Urban Territorial Spaces Based on Multisource Data: A Case Study of Suzhou City, China

The concept of green and low-carbon development is integrated into territorial spatial planning and district control research. It is one of the systematic policy tools for emission reduction and carbon sequestration, greatly contributing to achieving the double carbon goal. This paper presents a method for measuring the carbon emissions of urban territorial spaces using multisource big data, aiming to identify the spatial patterns and levels of carbon emissions at microspatial scales. The spatial patterns of carbon emissions were used to construct a carbon balance zoning method to evaluate the regional differences in the spatial distribution of carbon emissions, taking Suzhou as an example to achieve carbon balance zoning at the micro scale of the city. Based on our research, the following was determined: (1) Suzhou’s total carbon emissions in 2020 was approximately 240.3 million tons, with the industrial sector accounting for 81.32% of these emissions. The total carbon sink was about 0.025 million tons. (2) In Suzhou City, the high-value plots of carbon emissions are mainly located in industrial agglomeration areas. By contrast, low-value plots are primarily located in suburban areas and various carbon sink functional areas, exhibiting a scattered distribution. (3) The territorial space unit was divided into four functional areas of carbon balance, with 36 low-carbon economic zone units accounting for 37.11%, 29 carbon-source control zone units accounting for 29.90%, 14 carbon-sink functional zone units accounting for 14.43%, and 18 high-carbon optimization zone units accounting for 18.56%. As a result of this study, carbon balance zoning was achieved at the grassroots space level, which will assist the city in low-carbon and refined urban governance. Some ideas and references are also provided to formulate policies for low-carbon development at the micro scale of a city.

INFLUENCE OF CONFIGURATION OF THE ELECTRODE SYSTEM OF A COAXIAL MAGNETO PLASMA ACCELERATOR ON ARC DISCHARGE FORMATION AND DEVELOPMENT

Link for citation: Tsimmerman A.I., Shanenkov I.I., Nassyrbayev A.R., Nikitin D.S., Sivkov A.A. Influence of configuration of the electrode system of a coaxial magneto plasma accelerator on arc discharge formation and development. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 8, рр. 39-50. In Rus. The relevance of the research is explained by a wide range of practical areas, where various plasma generators can be used, including analytical devices, technological installations, tokamaks, ion and plasma engines, satellites, laser technology, as well as by the possibility of applying them for both producing coatings on various surfaces and synthesizing fine and nanopowders. The main aim of the research is to determine the best way to initiate an arc discharge in the acceleration channel of the coaxial magnetoplasma accelerator, to estimate the effect of the plasma formation zone configuration on the electrodynamic loads of the accelerator, and to calculate the efficiency of conversion of stored energy to supplied one. Objects: coaxial magnetoplasma accelerator, arc discharge initiation, central electrode, electrode-barrel, plasma formation zone. Methods: experiment, plasma dynamic synthesis, measurement and registration of pulsed currents and voltages, electrical erosion measurement by means of weighing the eroding electrode-bore, high-speed photoregistration of the plasma jet. Results. Two methods of arc discharge initiation using metal wires and graphitization were considered. It is established that they do not affect the energy parameters of the plasma dynamic synthesis, but the graphitization looks preferable due to the greater processability of the procedure that provides easy accelerator preparation and reliability of its operation. The possibility of reducing the arc discharge current amplitude by 29 % with increasing the plasma formation zone length from 5,5 to 11,5 mm was established that results in reducing electrodynamic loads on all system nodes. The optimal plasma formation zone length of 9,5 mm was determined to provide obtaining a high efficiency of conversion of stored energy into supplied energy and reliability of the system operation.

Deformation behavior and microstructure evolution of TZM alloy with 1.0 wt%ZrO2 under high temperature compression

The hot deformation behavior of TZM-1.0 wt% ZrO2 alloy in the temperature range of 1000–1600 °C and strain rate range of 0.005–1 s−1 was studied by hot compression method. The constitutive equation and hot working diagram were established, and the microstructure evolution was emphatically analyzed by SEM and EBSD. The results indicate that the flow stress decreases with the increase of temperature and the decrease of strain rate, and ZrO2 particles can improve the stability of TZM alloy in rate-control during hot deformation. The constitutive equation accurately predicted the correlation coefficient as high as 0.9685, calculated the average activation energy Q = 426 kJ mol−1, and obtained the best process parameters of 1150 °C–1250 °C /0.01–0.05 s−1 under 0.7 strain. The unstable zone was mainly composed of a small number of coarse grains and a large number of fine grains. The main reason for flow instability was the disharmonious deformation between coarse and fine grains during compression. The optimum hot working zone consists of more uniform equiaxed grains. However, EBSD observed that at a strain rate of 1 s−1, the recrystallization fraction at 1600 °C was lower than 1200 °C, and the dynamic recrystallization (DRX) and texture evolution trends at 1200 °C and 1600 °C were completely different. The abnormal changes in recrystallization fraction and texture evolution at 1600 °C were due to the competition between deformed grain growth and DRX on energy storage consumption, and the effect of deformed grain growth on energy storage consumption was greater than that of DRX. At 1600 °C/1 s−1, the growth of deformed grains was dominant, exhibiting strong texture components in the [001] direction, with〈100〉fibers as the main component and the highest peak texture strength. As the strain rate decreases, DRX dominates and weakens the texture strength, resulting in a significant decrease in<100>fibers.

Incorporating a new landscape intensity indicator into landscape metrics to better understand controls of water quality and optimal width of riparian buffer zone

River water quality plays a crucial role in numerous industries, necessitating the precise delineation of riparian buffer zones and the implementation of comprehensive management measures to preserve water quality. Determining the optimal riparian buffer zone through the impact of landscape metrics on water quality has been widely applied to river management. However, failure to differentiate the same indicators in areas with different anthropogenic activities could lead to inaccuracies in identifying the optimal riparian buffer zone, particularly in regions with notable gradient in anthropogenic activities. Here, we incorporated a new landscape intensity (NLI) indicator into the landscape metrics to better understand controls of water quality and optimal width of riparian buffer zone, considering the differences between areas with different anthropogenic activities. Based on water quality monitoring data from June 2010 to April 2013 in a typical agricultural-urban gradient with different anthropogenic activities, we adopted redundancy analysis (RDA) to quantify the spatial scale effects and seasonal dependence of various landscape metrics impact on river water quality, and then to reveal the importance of landscape metrics in explaining water quality by variance partitioning analysis (VPA). Results showed that landscape metrics were more effective at explaining the water quality variations during the dry season than the wet season (56.48% ∼ 68.99% vs 53.28% ∼ 58.91%). The 1000 m riparian buffer zone was found to be optimal for explaining water quality changes during the dry season, while the 200 m riparian buffer zone was optimal during the wet season. In addition, we found that NLI was the most important landscape metric in our study and could explain 26% to 52% of the variation in water quality. This study provides a new insight for developing a landscape metric that considers differences in anthropogenic activities, which can help us to better understand water quality changes and preserve aquatic ecosystems.

A diffusion-advection predator-prey model with a protection zone

In this paper, we investigate a diffusion-advection predator-prey model imposed the Danckwerts boundary conditions with three different types of protection zone. Some special cases have been extensively studied, such as: diffusion-advection predator-prey model without protection zone [22,29] and diffusive predator-prey model with protection zone without advection in high dimension [5,16]. Some ideas developed in the former works do not appear to work due to the difficulty caused by diffusion, advection and protection zone. By applying the comparison principle for parabolic equations [32] and persistence theory [26,37], we obtain almost complete long-time dynamics, which describes the optimal protection zone. If the predator functional response is Holling-type I, the uniqueness of the positive steady state has been derived, which improves the method proposed by López-Gómez and Pardo [20] and developed by Nie et al. [28]. Finally, new ways of coexistence have been obtained by investigating a special three-species model.

BIOFERTILIZER FOR CULTURE OF COMMON CORIANDER (Coriandrum sativum) USING WASTE FROM CASSAVA (Manihot esculenta) PROCESSING

Manipueira is a cassava processing residue with a polluting potential, and it is crucial to find alternatives for its disposal and reuse. The present study aimed to investigate the potential of this residue as a biofertilizer, through the fertirrigation method, in the culture of common coriander (C. sativum). The research took place through the dilution of manipueira in water in 9 concentrations, from 10% to 90%; in addition, there was the conservation of samples with 0%, containing only water, and 100%, containing pure manipueira. The results showed that coriander seeds fertirrigated with solutions above 70% presented larval emergence in the soil after the 18th day; Another important piece of data is that on the 20th day, the death of all specimens fertirrigated with solutions above 30% was observed, this fact being preceded by leaf stunting (solutions above 80%) and yellowing of leaves. These data can be explained by the soil sodification process (pH &gt; 8.5), which occurred in these samples. Furthermore, all samples did not stabilize the pH within the optimal zone for most cultures (between 5.5 and 7.0), which may explain the death of the specimens on the 25th day. That said, the environmental impact of manipueira on the germination process and botanical development is reinforced, which reiterates the importance of research that aims to find alternatives for the reuse of this residue. Thus, it is necessary to deepen research and even expand the range of cultures tested in each dilution.

The potential of betle leaf (Piper betle L.) against Staphylococcus aureus to cure mastitis: A systematic review

Mastitis is a problem in breastfeeding causes nutritional deficiencies in the baby. Staphylococcus aureus is one of the bacteria that causes mastitis. Betle leaf (Piper betle L.) has been used in several health problems and has antimicrobial activity. This study aims to explore the potential of betel leaf (Piper betle l.) against Staphylococcus aureus to cure mastitis. A systematic review was carried out according to the PRISMA guidelines. Searches were conducted in three databases namely PubMed, Google Scholar, and Science Direct. Search using keywords according to the Mesh term, namely 'betle leaf (Piper betle l.)', 'Staphylococcus aureus' and 'Mastitis'. 198 articles were found in a database search. 8 studies were analyzed. All studies found that both types of pipers betle, both green and red, showed positive effects in the treatment of mastitis. Processing techniques, storage, and certain concentrations such as boiling temperature affect the optimum inhibition zone of bacteria. The addition of certain formulas also increases the antimicrobial activity. The use of antibiotics and betel leaf extract can be used simultaneously to treat mastitis. Betle leaf (Piper betle L.), has a positive effect on the management of mastitis, but processing techniques, concentrations, and adjuvants need to be studied further.

A novel support vector machine with generalized pinball loss for uncertain data classification

In real‐world problems, data suffer from measurement errors, data staleness, and repeated measurements, which make data uncertain. To consider the uncertainty of data, the concept of giving each data feature as a multidimensional Gaussian distribution has been utilized. In 2021, support vector machines with an insensitive zone pinball loss (UPinSVMs) for uncertain data classification was proposed, where is a positive number. The UPinSVMs bring noise insensitivity, stability for resampling, and increased model sparsity. However, the value of is known to be specified. In order to improve the performance, we combine the generalized pinball loss (( ‐Mod‐Pin‐SVM) into the uncertain classification, term as UGPinSVMs, where are two positive numbers. The generalized pinball loss is an optimal insensitive zone pinball loss and is an extension of existing loss functions that also addresses the issues of noise insensitivity and resampling instability. We solve the primal quadratic programming problems by transforming individuals into unconstrained optimization using an efficient stochastic gradient descent algorithm. More specially, we have introduced verified theorems that are related to our approaches and investigated scatter minimization. The results from several benchmark datasets show that our model outperforms the existing classifier in terms of accuracy and statistical analysis. Furthermore, the application of our framework to the crop recommendation dataset is also examined.

Distribution of wild carrots &lt;i&gt;Daucus carota&lt;/i&gt; L. over the territory of the Russian Federation

A map showing the zone of the main distribution of wild carrots Daucus carota L. in the Russian Federation was compiled on the basis of the materials available in open-access scientific publications. According to the data on the frequency of the species’ occurrence in a separate area, found in published sources, the zone of the main distribution was divided into the optimum zone, where the species occurred with the “frequently” indicators, and the pessimum zone, where it occurred with the “rarely” indicators. The locations of single finds of the species listed in areas outside the main distribution zone were marked using information from the GBIF international database. Since wild carrots are both wild relatives of cultivated carrots and weedy plants, the presented map will be in demand among both plant breeders and plant protection experts.

Experimental upscaling analyses for a surfactant-enhanced in-situ chemical oxidation (S-ISCO) remediation design

Surfactant-enhanced in-situ chemical oxidation (S-ISCO) is an emerging innovative remediation technology for the treatment of dense non-aqueous phase liquids (DNAPLs). S-ISCO combines the solubilization of contaminants by means of surfactants with the chemical oxidation by an oxidizing agent, thus, potentially increasing the efficiency of the state-of-the-art ISCO technique. Scientific investigations are needed to enable the technology transfer for potential field applications based on the development of a remediation design under well-defined boundary conditions.For this purpose, experimental upscaling analyses were performed using the special infrastructure of the research facility for subsurface remediation (VEGAS). Batch tests showed that oxidation of the selected surfactant E-Mulse 3® (EM3) by activated persulfate (Na-PS) reduced the solubilization of the model contaminants 1,4-DCB, naphthalene, and PCE. As a consequence, the processes of contaminant solubilization and degradation were temporally and spatially separated in the developed remediation design.A proof of concept was provided by performing an S-ISCO medium-scale experiment (100 cm length, 70 cm height, 12.5 cm width), with 1,2-DCB as model DNAPL contaminant to be treated. A groundwater circulation well (GCW) was used to inject a 60 g/L Na-PS solution and to effectively mix the reagents. Sampling of the experiment's outflow and the soil material after treatment showed that neither rebound effects nor residual mass loadings on the soil material could be detected after termination of the S-ISCO treatment.To further evaluate the S-ISCO remediation design under field-like conditions, a large-scale S-ISCO experiment was conducted (6 m length, 3 m height, 1 m width), allowing for an extensive sampling campaign to monitor relevant processes. An efficient contaminant removal from the former source zone could be reached by surfactant solubilization, decreasing contaminant levels from initially over 2000 mg/L 1,2-DCB to final concentrations below 5 mg/L 1,2-DCB. The heterogeneously distributed contaminant degradation, implemented by a three-filter GCW, was attributed to density-induced migration processes that impeded an optimal reaction zone. A density-dependent numerical transport could qualitatively match the observations. By comparing different simulation scenarios, an adapted operation of the GCW was established that provides for a more efficient distribution of the density-influenced oxidant injection.

Spatial–Temporal Change Analysis and Multi-Scenario Simulation Prediction of Land-Use Carbon Emissions in the Wuhan Urban Agglomeration, China

In the context of global warming, the Wuhan Urban Agglomeration is actively responding to China’s carbon peak and carbon neutrality goals and striving to achieve a reduction in carbon sources and an increase in carbon sinks. Therefore, it is critical to investigate carbon emissions from land use. This study uses the carbon emission coefficient method to calculate carbon emissions from land use in the Wuhan Urban Agglomeration, analyzes its temporal and spatial changes and differences in urban structure, and couples with the Markov–PLUS model to simulate and predict the carbon emissions of four scenarios of land use in 2035. The research found the following: (1) during the Wuhan “1+8” City Circle stage, carbon sources and emissions increased steadily, with average annual growth rates of 1.92% and 1.99%, respectively. Carbon sinks remained stable and then decreased, with an average annual growth rate of −0.46%. (2) During the Wuhan Metropolitan Area stage—except for 2020 and 2021, which were affected by COVID-19—carbon sources, sinks, and emissions continued to grow in general, and the average annual growth rates increased to 4.46%, 1.58%, and 4.51%, respectively. (3) In terms of urban structure differences, Wuhan is a high-carbon optimization zone; Xianning, Huangshi, and Huanggang are ecological protection zones; other cities, such as Ezhou, Xiaogan, and Xiantao are comprehensive optimization zones; and there is no low-carbon development zone. (4) The multi-scenario simulation results show that carbon sources and emissions are the highest under the economic development scenario, with values of 100.2952 and 9858.83 million tons, respectively, followed by cropland protection, natural development, and low-carbon development scenarios. Under low-carbon development, carbon sinks were the highest, with values of 1.9709 million tons, followed by natural development, economic development, and cropland protection scenarios. The research results are conducive to the formulation of carbon peak and neutrality goals as well as low-carbon development plans for the Wuhan Urban Agglomeration.

Propeller Ground Effect in Forward Flight

The study of the fixed-pitch small-scale propeller in-ground effect is extended to forward flight conditions at different incidence angles of the propeller. Force-based experiments, smoke flow visualization, surface flow visualization, and phase-locked particle image velocimetry (PIV) indicate the presence of three distinct performance zones as a function of the advance ratio and ground distance, where the ground effect changes drastically. The power required at constant thrust shows an increasing trend after a threshold advance ratio for each and then decreases steeply upon a further increase in the advance ratio. Phase-locked PIV revealed the presence of a fountain vortex and a ground vortex at distinct for each distance that correlates with an increase in power and a decrease in thrust, respectively. At advance ratios below the onset of the fountain vortex lies the optimal ground effect zone. An increase in the advance ratio beyond this threshold will result in power increments due to the formation of the fountain vortex. A further increase in the advance ratio initiates the onset of the ground vortex where the ground effect is significantly reduced. The onset of the fountain vortex and the ground vortex occurs at comparatively lower advance ratios for propellers at a positive incidence angle. A normalization method is developed for ground effect forward flight that collapses the in-ground-effect performance for various normalized heights, advance ratios, and incidence angles.

Pelagic ciliate (Ciliophora) communities in the Southern Ocean: Bioindicator to water mass, habitat suitability classification and potential response to global warming

Although the pelagic ciliate (microzooplankton) play important role in carbon flux of marine ecosystems, their ecological function, habitat suitability classification and response to global warming were poorly documented in the Southern Ocean (SO). During summer of 2020/2021, ciliate (including aloricate ciliates and tintinnids) communities in waters from surface to 1000 m were investigated in the SO. Rapid attenuation of ciliate abundance and biomass occurred at 100 m depth in most stations. According to distinctive hydrographic features, five water masses were identified in the SO with unique ciliate community structure. Aloricate ciliate small size-fraction (10–20 μm) was dominant in water masses deeper than 200 m. Tintinnids showed distinctive regional and vertical distribution characteristics, and their habitat suitability characterized by the Bio-index exhibiting different optimum survival zones. Variations in tintinnid habitat can be regarded as indicators for future SO climate change. Correlation between environment factors and biota revealed that depth, Chl a and dissolved oxygen were main factors determining ciliate composition. Combining tendency of phytoplankton and meso-/macro-zooplankton to rapid global warming, ciliates may become smaller and more prominent in the future SO marine pelagic ecosystem. Our study has laid a foundation for recognizing the ciliate community and reinforcing the ideas about tintinnid indication for the change of future SO marine ecosystem.

Small-scale variation in available water capacity of the soil influences height growth of single trees in Southern Germany

Aim of study: Detecting possible small-scale soil effects on height growth of single trees in monospecific stands of three important tree species (Abies alba, Fagus sylvatica, and Picea abies).&#x0D; Area of study: 37 mature stands along an ecological gradient in Southern Germany from the cold and wet “optimal niche zone” to warmer and drier niche zones, including gravelly soils with poor water supply.&#x0D; Material and methods: Measurement of achieved height and age of 15 to 20 sample trees per stand. Estimation of the available water capacity of the soil (AWC) in close proximity to sample trees based on soil texture following the German soil survey guidelines. Examining height growth depending on niche zone and AWC. &#x0D; Main results: On sites (stand level) with the lowest water regime, height growth increased significantly with AWC of microsites. The estimated effect on height growth over the whole range of AWC values was almost 8 m at those sites. In contrast, the effect was negative on optimal sites. For intermediate and marginal sites, the effect was positive, albeit not significant for marginal sites.&#x0D; Research highlights: To our knowledge this is the first study about small-scale effects of AWC on height growth of single trees in temperate European forests. Small-scale soil variability should be considered in future scientific studies and practical evaluation, involving single tree performance at stands with low water regime. This seems particularly important in genetic environmental associations studies and in the process of selecting trees for breeding purposes in such stands.

Generation of Optimal Weight Values Based on the Recursive Monte Carlo Method for Use in Monte Carlo Deep Penetration Calculations

In nuclear engineering, Monte Carlo (MC) methods are commonly used for reactor analysis and radiation shielding problems. These methods are capable of dealing with both simple and complex system models with accuracy. The application of MC methods experiences challenges when dealing with the deep penetration problems that are typically encountered in radiation shielding cases. It is difficult to produce statistically reliable results due to poor particle sampling in the region of interest. Therefore, such calculations are performed by the Monte Carlo N-Particle Transport (MCNP) code in association with the weight window (WW) variance reduction technique, which increases the particle statistics in the desired tally region. However, for large problems, MCNP’s built-in weight window generator (WWG) produces zero WW parameters for tally regions located far from the source. To address this issue, the recursive Monte Carlo (RMC) method was proposed. This paper focuses on the RMC methodology and its implementation in the Helmholtz-Zentrum Dresden-Rossendorf’s (HZDR’s) in-house code TRAWEI, which is responsible for producing optimal zone weight parameters used for optimizing deep penetration MC calculations. In addition, this paper discusses the verification of the TRAWEI weight generator program to that of an existing MCNP WWG. The performance of TRAWEI-generated weight values is assessed using a handful of test cases involving two shield materials. Globally, the TRAWEI-generated weight values improved not only the statistical variance and computational efficiency of the MC run compared to the analog MCNP simulation but also those of the simulation with WW values generated by the standard MCNP WWG.

Optimal Landing Zone Selection and Online Trajectory Programming Method for Lunar Lander

To achieve a safe landing on the lunar surface with complex terrain, online landing zone selection is required. A DEM-based landing zone selection technique is proposed. The method firstly obtains several candidate landing zones by analyzing the gradient and variance information from the DEM, and then selects the integrated candidate landing zone by the overlap ratio. Finally, the optimal trajectory programming is carried out with the current state of the lander as the initial value and each integrated candidate landing zone as the final position, and the optimal landing zone is selected by comparing the required fuel to each landing zone. Compared with the classical DEM-based online landing site selection technique, the proposed method does not perform terrain reconstruction, responds quickly, and achieves real-time performance, and it also reduces fuel consumption, provides residual fuel for the subsequent landing phase, and increases the reliability of the landing process. Simulation results show that the proposed method is able to select several candidate landing zones in complex terrain, meanwhile, it is capable of achieving the optimal trajectory programming with the target of these several candidate landing zones, and finally, the optimal landing zone is selected by comparing the fuel consumption of each path.